Talc compositions

ABSTRACT

Talc powder compositions exhibiting excellent moisture absorbency comprising talc and a specific pregelatinized cornstarch.

BACKGROUND OF THE INVENTION

The present invention relates to body powder compositions. Moreparticularly, the present invention relates to talc compositions withimproved moisture absorbent properties.

Body powders have long been available to the consuming public primarilyfor absorbing moisture. Said moisture can, for example, be as a resultof the secretion from the sebaceous and sweat glands. Body powders havealso been used extensively on babies to help prevent diaper rash and tootherwise help maintain dryness.

High grade talcs have for many years been used in the form of powder forapplication to the skin. Talc, in its finely divided form, is wellsuited for this purpose. Thus, finely divided talc has found wideacceptance and application in the cosmetic industry and as a powder fortreating tender skins, such as those of infants or children, to preventchafing or other irritation as would occur from diapers or wet clothing.

Aside from talc, various other ingredients have also been proposed andutilized for body powders including starches, cellulose derivatives,polymeric substances and the like. Although many satisfactory talc andnon-talc compositions are available through commercial channels,numerous attempts to develop improved talc compositions have beenongoing. See, for example, U.S. Pat. Nos. 3,102,855; 3,133,866;3,684,197; 3,801,709 and 4,185,086. Since one of the primary purposes ofa body powder is to absorb moisture, the effectiveness of the bodypowder is diminished when the powder has reached its capacity forabsorbence. Therefore, developments that increase the absorbency withoutdecreasing the other desirable properties of powders are desired.Numerous compositions and additives have been suggested in theliterature for this purpose and have met with varying degrees ofsuccess.

SUMMARY OF THE INVENTION

It is an object of this invention to provide improved body powdercompositions.

It is another object of this invention to provide talc powdercompositions with improved moisture absorbency.

Other objects of this invention will be set forth in, or be apparentfrom, the following detailed description of the invention.

The foregoing objects and other features and advantages of the presentinvention are achieved by a composition comprising a major amount oftalc and a minor amount of a specific pregelatinized cornstarch.

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to talc compositions consisting of fromabout 99 to 80% talc and from about 1 to 20% of a pregelatinizedcornstarch and may also contain other components normally utilized insuch compositions.

The talc which is useful in the present invention is a cosmetic grade oftalc which conforms to the Cosmetic Toiletry and Fragrance Association,Inc. specifications. Such talc is essentially a white, odorless, finepowder grond from a naturally occurring rock ore and it typicallyconsists of about 90% hydrous magnesium silicate having a structuralformula of Mg₆ (Si₈ O₂₀)·(OH)₄, with the remainder consisting ofnaturally associated minerals such as calcite, chlorite, dolomite,kaolin, and magnesite and containing no asbestos minerals. The preferredparticle size is such that 100% passes through a 60 mesh screen and notless than 99% passes through a 100 mesh screen and at least 98% passesthrough a 200 mesh screen. The talc is utilized in an amount of fromabout 99 to 80% by weight of the total composition, preferably at least85% by weight of the total composition.

The pregelatinized cornstarch which is useful in the present inventionis derived specifically from waxy maize corn. The pregelatinizedcornstarch is cornstarch that has been chemically or mechanicallyprocessed to rupture all or part of the granules, preferably in thepresence of water and subsequently dried. This pregelatinization of thecornstarch is achieved by well-known processing techniques in the starchindustry. Generally, this process involves dispersing a cornstarch,preferably waxy maize cornstarch, into a dilute water slurry which isthen doctored onto a drum drier internally heated by superheated steam.The surface temperature of the drum boils the slurry and simultaneouslyconverts it to a pregelatinized form and also dries the boiled starchmixture into a film which is then stripped from the drum by a scraperblade. It has now been found that subsequently milling or grinding thisfilm forms flaky particles of particle size such that at least 80%, andpreferably about 98%, passes through a 200 mesh screen. These particlesshould have a bulk density of from about 3.0 gm./cubic in. to about 7.0gm./cubic in. and a moisture content no greater than about 14% by weightand preferably no greater than about 7% by weight, to be suitable foruse in the compositions of the present invention.

The specific pregelatinized cornstarch is utilized in from about 1.0 to20% by weight of the total composition, preferably from about 1.0 to15%. If less than about 1.0% by weight of the total composition isutilized then the desired advantages will not be readily achieved. Ifgreater than about 20% by weight of the total composition is utilizedthen tactile properties such as texture, smoothness and lubricity couldbe adversely affected.

Other components normally found in talc compositions can be added, ifdesired. Such components include dyes and colorings, bactericides,medicaments and perfumes.

The perfumes which are useful in the present invention include anycommercial perfume which results in the fragrance desired by theformulator of the powder compositions. Commercial perfumes are mixtureof many components and these components all contribute to the particularfragrance which is characteristic of the mixture. In obtaining thedesired fragrance, the ratio of components might be changed, somecomponents may be added and some omitted.

Examples of typical perfume components which can be formulated to makeup a particular pleasant aroma when used in a body powder productinclude: lemon oil, musk ketone, ionone, diphenyl oxide,cedarwood-terpeneless, geranyl acetate, ylang ylang oil; cedryl acetate,isoeugenol, cinnamic alcohol, aurantheol, methyl anthranilate, vanillin,oil bergamot, eugenol, oil of cananga, citral, tetrahydro linalool, oilpatchouly, methyl isoeugenol, hexylcinnamic aldehyde, resil oil-banum,resin balsam fir, musk aurbrette, resin balsam Peru, oil sandalwood,geraniol, terpenyl acetate, benzyl isoeugenol, oil copaiba, oil nutmeg,rhodinol, diphenyl methane, hydroxycitronellal, methyl benzoate, benzylpropionate, oil palmarose, oil orange, oil geranium, methyl gammaionone, oil of lavender and the like.

The perfume is utilized in an amount of from about 0.01 to 1.0% byweight of the total composition, preferably from about 0.1 to 0.5% byweight of the total composition. If greater than about 1.0% by weight ofperfume is utilized, the fragrance will usually be too strong initiallyand may deteriorate quickly; and if less than 0.01% by weight of perfumeis utilized, the fragrance will not be discernible to the user of theproduct.

The compositions of the present invention can be prepared by well-knownmixing or blending procedures. For example, the talc and pregelatinizedcornstarch and other ingredients, if utilized, are mixed and thoroughlyblended and the perfume is then uniformly mixed therein. The resultingpowder compositions exhibit excellent moisture absorbency.

Specific embodiments of the talc compositions prepared in accordancewith the present invention are illustrated by the followingrepresentative examples. It will be understood, however, that theinvention is not confined to the specific limitations set forth in theindividual examples, but rather to the scope of the appended claims.

EXAMPLE I

A talc powder composition is prepared as follows: 98.78 parts of talcand 1.0 part of pregelatinized cornstarch are placed in a PK Blendermanufactured by Patterson-Kelley, East Stroudsburg, Pa., with a liquidaddition bar and the Blender is activated. 0.22 parts of fragrance arethen added through the liquid addition bar and mixing is continued forfive minutes, followed by tumbling for 15 minutes.

The resulting talc powder composition has the following formulation:

    ______________________________________                                                         % w/w                                                        ______________________________________                                        talc               98.78                                                      pregelatinized cornstarch                                                                        1.00                                                       fragrance          0.22                                                                          100.00                                                     ______________________________________                                    

EXAMPLE II

In order to demonstrate that the talc powder compositions prepared inaccordance with the present invention exhibit excellent moistureabsorbency, the following experiment is performed.

A talc powder composition is prepared in accordance with the procedureof Example I and is designated Composition A. Five additional talcpowder compositions, i.e., Compositions B, C, D, E and F are prepared bythe same procedure and contain 2.50%, 5.00%, 10.00%, 15.00% and 20.00%respectively, of the pregelatinized cornstarch. A further composition isprepared as a control containing no pregelatinized cornstarch and isdesignated Composition G.

These talc powder compositions are then tested in accordance with thefollowing gravimetric absorbency test procedure:

Approximately 0.3 gms of each talc powder composition is uniformlydispersed over the surface of a glass fiber filter disc. A circularlayer of powder 5.08 cm in diameter is obtained giving a powdered areaof 19.6 sq. cm. The powdered disc is then placed on a porous glass plateconnected by a continuous liquid bridge to a reservoir of 1% salinesolution located at 5 mm below the plate so a slight negative headpressure exists at the liquid/powder interface. This slight negativehead pressure assures that liquid taken up by the powder is due to its"demand absorbency" wicking potential and not to a positive headpressure force. The amount of solution absorbed by the powder iselectronically detected and recorded to an accuracy of 0.01 gms.Absorbency is stated in terms of cc of saline absorbed per gram ofpowder. The absorbent capacity in this thin layer test is determined bythe fluid uptake in 5 minutes. This test procedure and the apparatusutilized therein is more fully set forth in U.S. Pat. No. 4,357,827which is incorporated herein by reference.

The results of the test are shown in Table I below wherein theabsorbency of compositions A, B, C, D, E and F are compared toComposition G and the results shown below:

                  TABLE I                                                         ______________________________________                                                     % Pregelatinized                                                                           Absorbency                                          Composition  Cornstarch   cc/gm.                                              ______________________________________                                        A            1.0          0.10                                                B            2.5          0.12                                                C            5.0          0.41                                                D            10.0         1.51                                                E            15.0         2.43                                                F            20.0         3.05                                                G            0            0                                                   ______________________________________                                    

The above results clearly demonstrate that the compositions of thepresent invention containing the pregelatinized cornstarch exhibitsignificant increased absorbency when compared to the same compositionwithout the pregelatinized cornstarch. These compositions also exhibitgood flowability and tactile properties.

EXAMPLE III

In order to further demonstrate the advantages of the talc powdercompositions of the present invention, the following experiment isperformed.

Six talc powder compositions are prepared, i.e., Compositions H, I, J,K, L and M containing 1.0%, 2.5%, 5%, 10%, 15% and 20% of conventionalcommercially available cornstarch respectively and these compositionsare then tested in accordance with the gravimetric absorbency testprocedure set forth in Example II. These results as well as the resultsfrom the test conducted on Compositions A, B, C, D, E and F are showbelow in Table II:

                  TABLE II                                                        ______________________________________                                        Compo-  % Pregelatinized                                                                           % Conventional                                                                             Absorbency                                  sition  Cornstarch   Cornstarch   cc/gm.                                      ______________________________________                                        A       1.0          0            0.10                                        B       2.5          0            0.12                                        C       5.0          0            0.41                                        D       10.0         0            1.51                                        E       15.0         0            2.43                                        F       20.0         0            3.05                                        H       0            1.0          0.02                                        I       0            2.5          0.08                                        J       0            5.0          0.14                                        K       0            10.0         0.23                                        L       0            15.0         0.63                                        M       0            20.0         0.93                                        ______________________________________                                    

The above results clearly demonstrate that the compositions of thepresent invention containing the pregelatinized cornstarch exhibitsignificant increased absorbency when compared to the same compositionscontaining conventional cornstarch instead of the pregelatinizedcornstarch.

Various other features and embodiments of the present invention notspecifically enumerated will be obvious to those skilled in the art, allof which may be achieved without departing from the spirit and the scopeof the invention as defined by the following claims.

I claim:
 1. A body powder composition comprising from about 99 to 80% byweight of the total composition talc and from about 1 to 20% by weightof the total composition pregelatinized cornstarch.
 2. The compositionof claim 1 wherein the pregelatinized cornstarch is present from about1.0 to 15% by weight of the total composition.
 3. The composition ofclaim 1 wherein the talc is present from about 99 to 85% by weight ofthe total composition.
 4. The composition of claim 1 containing fromabout 0.01 to 1.00% perfume